Hi @Abbirami
You can apply an ACL for the specific workflow model to /var/workflow/models
this way to can provide the access to specific group that you want to trigger the workflow.
if you won't include participant step in you workflow model then it wont go to any approval process.
A Participant Step enables you to assign ownership for a particular action. The workflow proceeds only when the user has manually acknowledged the step. This workflow is used when you want someone to act on the workflow. For example, a review step.
More info about Access : https://experienceleague.adobe.com/docs/experience-manager-65/administering/operations/workflows-man...